Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway
River regulation alters flow and sediment regime, habitat availability, and ultimately the ecological functioning of rivers. Various restoration and mitigation measures have been developed to improve ecological function, and among them is the addition of gravel to enhance the reproduction of gravel...
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ftnorce:oai:norceresearch.brage.unit.no:11250/2984510 2023-05-15T15:30:23+02:00 Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway Pulg, Ulrich Lennox, Robert Stranzl, Sebastian Franz Espedal, Espen Olsen Gabrielsen, Sven-Erik Wiers, Tore Velle, Gaute Hauer, Christoph Dønnum, Bjørn Otto Barlaup, Bjørn Torgeir 2021 application/pdf https://hdl.handle.net/11250/2984510 https://doi.org/10.1007/s10750-021-04646-2 eng eng https://link.springer.com/article/10.1007/s10750-021-04646-2 Hydrobiologia. 2021, 849 485-507. urn:issn:0018-8158 https://hdl.handle.net/11250/2984510 https://doi.org/10.1007/s10750-021-04646-2 cristin:1999489 Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © The Authors, 2021 CC-BY Hydrobiologia 849 485-507 Peer reviewed Journal article 2021 ftnorce https://doi.org/10.1007/s10750-021-04646-2 2022-10-13T05:50:41Z River regulation alters flow and sediment regime, habitat availability, and ultimately the ecological functioning of rivers. Various restoration and mitigation measures have been developed to improve ecological function, and among them is the addition of gravel to enhance the reproduction of gravel bed spawning fishes. However, information on long-term efficiency, costs, and maintenance needs of gravel additions are scarce. Here, we study the functioning of gravel additions at eight sites in three rivers in western Norway for up to 18 years. Gravel was added between 2002 and 2010 to enhance spawning of Atlantic salmon and anadromous Brown trout. We monitored changes in the size of the gravel-covered areas, sediment composition, interstitial oxygen, egg survival, and juvenile fish densities. Additionally, we report monetary costs, identify potential maintenance needs, and calculate a cost-benefit ratio. Juvenile densities of Atlantic salmon and Brown trout increased significantly after the gravel augmentations. After 10–18 years, the median egg survival was still high (> 90%) and sediment conditions were still suitable for salmonid fish reproduction. The areas were, however, shrinking across time (median area reduction 26%), mostly caused by scouring of gravel in the steep, supply-limited, and partly regulated rivers. The average construction costs of spawning gravel augmentations were 11.2 NOK (1.12 €) m−2 year−1. Compared to similar measures elsewhere, the measures have had a long life span (up to 18 years) at relatively low costs. Gravel augmentation was concluded to be a successful management measure that contributed to significantly increased Atlantic salmon and Brown trout reproduction. publishedVersion Article in Journal/Newspaper Atlantic salmon NORCE vitenarkiv (Norwegian Research Centre) Norway Hydrobiologia 849 2 485 507 |
institution |
Open Polar |
collection |
NORCE vitenarkiv (Norwegian Research Centre) |
op_collection_id |
ftnorce |
language |
English |
description |
River regulation alters flow and sediment regime, habitat availability, and ultimately the ecological functioning of rivers. Various restoration and mitigation measures have been developed to improve ecological function, and among them is the addition of gravel to enhance the reproduction of gravel bed spawning fishes. However, information on long-term efficiency, costs, and maintenance needs of gravel additions are scarce. Here, we study the functioning of gravel additions at eight sites in three rivers in western Norway for up to 18 years. Gravel was added between 2002 and 2010 to enhance spawning of Atlantic salmon and anadromous Brown trout. We monitored changes in the size of the gravel-covered areas, sediment composition, interstitial oxygen, egg survival, and juvenile fish densities. Additionally, we report monetary costs, identify potential maintenance needs, and calculate a cost-benefit ratio. Juvenile densities of Atlantic salmon and Brown trout increased significantly after the gravel augmentations. After 10–18 years, the median egg survival was still high (> 90%) and sediment conditions were still suitable for salmonid fish reproduction. The areas were, however, shrinking across time (median area reduction 26%), mostly caused by scouring of gravel in the steep, supply-limited, and partly regulated rivers. The average construction costs of spawning gravel augmentations were 11.2 NOK (1.12 €) m−2 year−1. Compared to similar measures elsewhere, the measures have had a long life span (up to 18 years) at relatively low costs. Gravel augmentation was concluded to be a successful management measure that contributed to significantly increased Atlantic salmon and Brown trout reproduction. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Pulg, Ulrich Lennox, Robert Stranzl, Sebastian Franz Espedal, Espen Olsen Gabrielsen, Sven-Erik Wiers, Tore Velle, Gaute Hauer, Christoph Dønnum, Bjørn Otto Barlaup, Bjørn Torgeir |
spellingShingle |
Pulg, Ulrich Lennox, Robert Stranzl, Sebastian Franz Espedal, Espen Olsen Gabrielsen, Sven-Erik Wiers, Tore Velle, Gaute Hauer, Christoph Dønnum, Bjørn Otto Barlaup, Bjørn Torgeir Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
author_facet |
Pulg, Ulrich Lennox, Robert Stranzl, Sebastian Franz Espedal, Espen Olsen Gabrielsen, Sven-Erik Wiers, Tore Velle, Gaute Hauer, Christoph Dønnum, Bjørn Otto Barlaup, Bjørn Torgeir |
author_sort |
Pulg, Ulrich |
title |
Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
title_short |
Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
title_full |
Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
title_fullStr |
Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
title_full_unstemmed |
Long-term effects and cost-benefit analysis of eight spawning gravel augmentations for Atlantic salmon and Brown trout in Norway |
title_sort |
long-term effects and cost-benefit analysis of eight spawning gravel augmentations for atlantic salmon and brown trout in norway |
publishDate |
2021 |
url |
https://hdl.handle.net/11250/2984510 https://doi.org/10.1007/s10750-021-04646-2 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Atlantic salmon |
genre_facet |
Atlantic salmon |
op_source |
Hydrobiologia 849 485-507 |
op_relation |
https://link.springer.com/article/10.1007/s10750-021-04646-2 Hydrobiologia. 2021, 849 485-507. urn:issn:0018-8158 https://hdl.handle.net/11250/2984510 https://doi.org/10.1007/s10750-021-04646-2 cristin:1999489 |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © The Authors, 2021 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1007/s10750-021-04646-2 |
container_title |
Hydrobiologia |
container_volume |
849 |
container_issue |
2 |
container_start_page |
485 |
op_container_end_page |
507 |
_version_ |
1766360834205810688 |